<form name="frm_seguridad" id="frm_seguridad" action="site.php?mod=1&sub=1&acc=1" method="post">
  <table width="66%" border="1">
		<tr>
            <td class="Accion">Lista de Roles</td>
		</tr>
        <tr>
            <td>
				<table id="tbl_roles">
					<?php if(isset($cbo_roles) != ""){echo $cbo_roles;} ?>
				</table>
			</td>
        </tr>
	</table>
</form>